TECHNICAL FIELD
[0001] Embodiments pertain to secure reception and generation of radio waveforms. Some embodiments
relate to parameterized generation of waveforms and control of waveform reception.
BACKGROUND
[0002] Electronic Warfare (EW) systems process massive amounts of Radio Frequency (RF) data
in short periods of time and play an increasingly important role in modern warfare.
It is not uncommon for an airborne EW system to process well over a million pulses
in a single second continuously throughout a mission. The data processed by the EW
system may include both threat-related and non threat-related RF signals. Consequently
the complexity of the EW responses to threat waveforms is growing exponentially and
a technique is desired to quickly create customized and sometimes complex EW responses,
or jamming, in real time.
[0003] In most circumstances, it may be desirable for the EW system to be able to respond
to numerous existing RF threats as well as respond quickly to new RF threats. The
use of radar techniques to detect vehicles are becoming increasingly advanced, leading
to the use of EW techniques to counter the more advanced radars. It would be desirable
to be able to further enhance the existing ability to provide EW countermeasures.
[0004] WO 2011/125060 A2 discloses a tactical electronic counter measure system comprising a first retro-directional
transceiver sub system, receiving signals at a first frequency band, and first retro-directional
transceiver retransmitting a signal at least substantially toward the direction from
which the sources signal was received, and first retro directional transceiver sub
system including a plurality of blade antennas and a controller, coupled with and
first retro-directional transceiver, and controller controlling the activity of and
first retro directional transceiver sub system, and controller further managing the
missions of and first retro directional transceiver sub system.
[0005] CA 1 119 702 A discloses using an analog frequency dividing system to virtually instantaneously
down-convert received signals in octave steps and in octave stages into the frequency
regimes associated with the operation of processing devices, such as analog to digital
converters, digital logic devices, surface acoustic wave devices, and charge coupled
devices. Those processed signals which are selected for retransmission, perhaps in
a modified form, are then up-converted into the region of the received signal by the
appropriate number of stages of frequency multipliers. Any modification in such signal
parameters as signal duration, delay, frequency, phase, power, amplitude or spectral
content may be incorporated prior to the first multiplication stage, between multiplication
stages, after the last multiplication stage, or any combination of the above.
[0006] US 2014/362774 A1 discloses a system and method for providing efficient wideband inverse channelization
for direct digital synthesizer based jamming techniques are generally described herein.
In some embodiments, metadata associated with a technique for generating a waveform,
such as frequency, phase and amplitude parameters, is received. Data select signals
and data input are generated based on the received metadata. In-phase and quadrature
signals are produced at an output of a first de-multiplexer and a second de-multiplexer,
respectively, based on the data select signals and the data input. Frequency modulated
signals generated by direct digital synthesizers may be combined in a channel using
a separate, distinct channel combiner.
[0007] US 5 003 312 A discloses a velocity deception apparatus utilizing a serrodyne technique to produce
various deception jamming modes. The modes are all controllable by parameters which
are digitally stored and in addition, the modes may be selectively actuated by a remote
control panel located in the aircraft on which the apparatus is installed. All of
the foregoing is accomplished with low cost, reliability, simplicity and with flexibility
of operation in being able to digitally reprogram the apparatus on an ongoing basis.
SUMMARY
[0008] In an aspect, the present disclosure provides an electronic warfare 'EW' system comprising:
electronic attack 'EA' circuitry comprising detection circuitry arranged to detect,
capture and store threat pulses from a radar, pulse generation circuitry arranged
to, in response to identification of the threat pulses, generate a response comprising
a superposition of the threat pulses captured and stored in memory by at least modulating
the threat pulses in amplitude, frequency, phase, length and timing, wherein modulations
of each threat pulse and timing of the superposition relative to the threat pulses
are based on stored parameters, the superposition comprising response pulses associated
with at least one of: threat pulses comprising different characteristics; and threat
pulses originating from different radar; and transceiver circuitry configured to receive
the threat pulses and transmit response pulses of the response; wherein the pulse
generation circuitry comprises a pulse memory arranged to provide the threat pulses
and a plurality of modules comprising: pulse stretch circuitry arranged to adjust
pulse widths of the response pulses away from pulse widths of the threat pulses; range
modulation circuitry arranged to adjust delays of the response pulses away from delays
of the threat pulses; velocity modulation circuitry arranged to adjust frequencies
of the response pulses away from frequencies of the threat pulses; and amplitude modulation
circuitry arranged to adjust amplitudes of the response pulses away from amplitudes
of the threat pulses; wherein the range modulation circuitry is selectable in Range
Gate Stealer/Range Gate Pull Out 'RGS/RGPO' mode in which the response pulses are
walked from zero to maximum delay with one of constant velocity and acceleration and
constantly repeated, RGS/RGPO with Keeper mode that duplicates the RGS/RGPO mode and
adds a keeper pulse at a stop range position of each response pulse, pseudorandom
mode in which the response pulses are randomly placed between a specified range or
Range Bin Masking in which the response pulses are randomly placed between specified
range values at ranges that are integral multiples of a range bin size.
[0009] In another aspect, the present disclosure provides a method of generating pulses
comprising: detecting and storing threat pulses from at least one radar impinging
on a vehicle; determining that the threat pulses are valid threat pulses; modulating
amplitude, frequency, phase, length and timing of the stored threat pulses and superposing
the modulated threat pulses to generate response pulses to the threat pulses, modulations
of each threat pulse and timing of the superposition relative to the threat pulses
based on stored parameters; transmitting the response pulses; providing the threat
pulses from a memory; modulating pulse widths of the response pulses from pulse widths
of the threat pulses; modulating frequencies of the response pulses from frequencies
of the threat pulses; modulating amplitudes of the response pulses from amplitudes
of the threat pulses; selecting a mode for modifying the delays from a Range Gate
Stealer/Range Gate Pull Out 'RGS/RGPO' mode in which the response pulses are walked
from zero to maximum delay with one of constant velocity and acceleration and constantly
repeated, a RGS/RGPO with Keeper mode that duplicates the RGS/RGPO mode and adds a
keeper pulse at a stop range position of each response pulse, a pseudorandom mode
in which the response pulses are randomly placed between a specified range and a Range
Bin Masking in which the response pulses are randomly placed between specified range
values at ranges that are integral multiples of a range bin size.
[0010] In yet another aspect, the present disclosure provides a computer-readable storage
medium that stores instructions for execution by one or more processors to: detect
threat pulses from at least one radar; modulate amplitude, frequency, phase, length
and timing of the threat pulses and superposing the modulated threat pulses to generate
response pulses to the threat pulses, modulations of each threat pulse and timing
of the superposition relative to the threat pulses based on stored parameters; calculate
predicted timing of the threat pulses based on reception of the threat pulses; disable
reception of the threat pulses at predetermined times; generate response pulses and
transmit the response pulses in response to threat pulses when the threat pulses are
received and when reception of the threat pulses is disabled; modify characteristics
of the threat pulses from initial characteristics of threat pulses, the characteristics
including pulse widths, delays, frequencies and amplitudes; select a mode for modifying
the delays from a Range Gate Stealer/Range Gate Pull Out 'RGS/RGPO' mode in which
the response pulses are walked from zero to maximum delay with one of constant velocity
and acceleration and constantly repeated, a RGS/RGPO with Keeper mode that duplicates
the RGS/RGPO mode and adds a keeper pulse at a stop range position of each response
pulse, a pseudorandom mode in which the response pulses are randomly placed between
a specified range and a Range Bin Masking in which the response pulses are randomly
placed between specified range values at ranges that are integral multiples of a range
bin size each response pulse, and select a mode for modifying the amplitude from square,
sinusoidal, triangular and sawtooth amplification.
BRIEF DESCRIPTION OF THE DRAWINGS
[0011]
FIG. 1 is a functional block diagram illustrating a communication system in accordance
with some embodiments;
FIG. 2 illustrates a block diagram of a wireless device in accordance with some embodiments;
FIG. 3 shows a block diagram of EA firmware architecture according to some embodiments;
FIG. 4 shows the CTG architecture in accordance with some embodiments; and
FIG. 5 illustrates EW system response in accordance with some embodiments.
DETAILED DESCRIPTION
[0012] The following description and the drawings sufficiently illustrate specific embodiments
to enable those skilled in the art to practice them. Other embodiments may incorporate
structural, logical, electrical, process, and other changes. Portions and features
of some embodiments may be included in, or substituted for, those of other embodiments.
Embodiments set forth in the claims encompass all available equivalents of those claims.
[0013] FIG. 1 is a functional block diagram illustrating a communication system in accordance
with some embodiments. FIG. 1 is a functional block diagram illustrating one embodiment
of an RF environment 100 in which vehicle 110 contains EW system 112 and is in the
range of radar 120. The EW system 112 may provide coherent technique(s) to respond
to different pulses and pulse types from a wide variety of radar sources, including
radar 120, via one or more antennas 114. The EW system 112 may capture the pulses
from the radar 120 in a pulse catalogue composed into a single modulated pulse train
and retransmit pulses as countermeasures.
[0014] The EW system 112 includes a receiver 112a to receive threat pulses from RF threats,
including radar 120, a transmitter 112b to transmit countermeasures (response pulses)
against the RF threats and electronic attack (EA) firmware (shown in FIGS. 3 and 4)
that may be separate from or a part of the receiver 112a and a transmitter 112b. The
receiver 112a and transmitter 112b may be referred to as a transceiver or transceiver
circuitry. Coherent techniques refer to the class of countermeasures in which the
EW systems modifies in whole or in part, in one more fashions, the currently received
pulse or a previously received pulse(s) and retransmits the modified signal. Modifications
may include, but are not limited to, frequency shifts (according to a schema that
varies the modification on successive pulses), adding noise (many types, also according
to a schema), modulation, re-ordering samples, delaying samples in time (according
to a schema), delaying and shifting frequency in a coordinated fashion (according
to a schema), and mixing and matching the above in serial, parallel, or both In many
cases the techniques rely on an Anticipated Time of Arrival (ATOA), as described in
more detail below. Thus, for example, radar 120 may emit a transmission signal 122
that impinges on vehicle 110 and reflects from vehicle 110 as reflection signal 124.
Vehicle 110 may absorb transmission signal 122 so that no reflection signal 124 is
transmitted back to radar 120, as shown transmit a countermeasure signal 114 to negate
reflection signal 124, or take no action, depending on the countermeasure the EW system
112 determines to take.
[0015] The EW system 112 may be embedded within vehicle 110, which may be a military land,
sea or air vehicle configured to gather intelligence data and perform other missions.
During missions, the EW system 112 be used offensively or defensively. For example,
the data gathered by the EW system 112 may be used for instantaneous assessment of
target systems such as radar 120 to determine whether to take offensive or defensive
action against one or more of the target systems. Defensive measures taken may include,
for example, jamming the target system to decrease the quality of measurements performed
by the system and decrease the chances of detection or targeting by the system. Offensive
measures may include more stringent methods of avoiding (e.g., by route alteration
of the vehicle) or eliminating the offending systems.
[0016] FIG. 2 illustrates a block diagram of an EW system in accordance with some embodiments.
In some embodiments, the EW system 200 may be a computer configured to perform any
one or more of the techniques during transaction events discussed herein. In alternative
embodiments, the EW system 200 may operate as a standalone device or may be connected
(e.g., networked) to other computers. In a networked deployment, the EW system 200
may operate in the capacity of a server, a client, or both in server-client network
environments. In an example, the EW system 200 may act as a peer machine in peer-to-peer
(P2P) (or other distributed) network environment. The EW system 200 may be a general
or specialized computer or any machine capable of executing instructions (sequential
or otherwise) that specify actions to be taken by that machine. Although a number
of components are shown as being included in EW system 200, some of these components
may or may not be present.
[0017] Examples, as described herein, may include, or may operate on, logic or a number
of components, modules, or mechanisms. Modules and components are tangible entities
(e.g., hardware) capable of performing specified operations and may be configured
or arranged in a certain manner. In an example, circuits may be arranged (e.g., internally
or with respect to external entities such as other circuits) in a specified manner
as a module. In an example, the whole or part of one or more computer systems (e.g.,
a standalone, client or server computer system) or one or more hardware processors
may be configured by firmware or software (e.g., instructions, an application portion,
or an application) as a module that operates to perform specified operations. In an
example, the software may reside on a machine readable medium. In an example, the
software, when executed by the underlying hardware of the module, causes the hardware
to perform the specified operations.
[0018] Accordingly, the term "module" (and "component") is understood to encompass a tangible
entity, be that an entity that is physically constructed, specifically configured
(e.g., hardwired), or temporarily (e.g., transitorily) configured (e.g., programmed)
to operate in a specified manner or to perform part or all of any operation described
herein. Considering examples in which modules are temporarily configured, each of
the modules need not be instantiated at any one moment in time. For example, where
the modules comprise a general-purpose hardware processor configured using software,
the general-purpose hardware processor may be configured as respective different modules
at different times. Software may accordingly configure a hardware processor, for example,
to constitute a particular module at one instance of time and to constitute a different
module at a different instance of time.
[0019] The EW system 200 may include a hardware processor 202 (e.g., a central processing
unit (CPU), a Field Gate Programmable Array (FPGA), an Application-Specific integrated
circuit (ASIC), a graphics processing unit (GPU), a hardware processor core, or any
combination thereof), a main memory 204 and a static memory 206, some or all of which
may communicate with each other via an interlink (e.g., bus) 208. Although not shown,
the main memory 204 may contain any or all of removable storage and non-removable
storage, volatile memory or non-volatile memory. The EW system 200 may further include
a display unit 210, an alphanumeric input device 212 (e.g., a keyboard), and a user
interface (UI) navigation device 214 (e.g., a mouse). In an example, the display unit
210, input device 212 and UI navigation device 214 may be a touch screen display.
The EW system 200 may additionally include a storage device (e.g., drive unit) 216,
a signal generation device 218 (e.g., a speaker), a network interface device 220,
and one or more sensors 221, such as a global positioning system (GPS) sensor, compass,
accelerometer, or other sensor. The EW system 200 may include an output controller
228, such as a serial (e.g., universal serial bus (USB), parallel, or other wired
or wireless (e.g., infrared (IR), near field communication (NFC), etc.) connection
to communicate or control one or more peripheral devices (e.g., a printer, card reader,
etc.).
[0020] The storage device 216 may include a machine readable medium 222 on which is stored
one or more sets of data structures or instructions 224 (e.g., software) embodying
or utilized by any one or more of the techniques or functions described herein. The
instructions 224 may also reside, completely or at least partially, within the main
memory 204, within static memory 206, or within the hardware processor 202 during
execution thereof by the EW system 200. In an example, one or any combination of the
hardware processor 202, the main memory 204, the static memory 206, or the storage
device 216 may constitute machine readable media.
[0021] While the machine readable medium 222 is illustrated as a single medium, the term
"machine readable medium" may include a single medium or multiple media (e.g., a centralized
or distributed database, and/or associated caches and servers) configured to store
the one or more instructions 224.
[0022] The term "machine readable medium" may include any medium that is capable of storing,
encoding, or carrying instructions for execution by the EW system 200 and that cause
the EW system 200 to perform any one or more of the techniques of the present disclosure,
or that is capable of storing, encoding or carrying data structures used by or associated
with such instructions. Non-limiting machine readable medium examples may include
solid-state memories, and optical and magnetic media. Specific examples of machine
readable media may include: non-volatile memory, such as semiconductor memory devices
(e.g., Electrically Programmable Read-Only Memory (EPROM), Electrically Erasable Programmable
Read-Only Memory (EEPROM)) and flash memory devices; magnetic disks, such as internal
hard disks and removable disks; magneto-optical disks; Random Access Memory (RAM);
and CD-ROM and DVD-ROM disks. In some examples, machine readable media may include
non-transitory machine readable media. In some examples, machine readable media may
include machine readable media that is not a transitory propagating signal.
[0023] To effect opportunistic use of the EW system, a vast amount of data from target systems
may be obtained and processed in situ during a mission. The EW system may obtain signals
that originate from known or unknown sources, evaluate the signals based on EW information
stored in its memory and determine a desired course of action to either take appropriate
measures automatically or indicate to the user one or more actions to take and wait
for the user to respond with the appropriate course of action. The EW system may use
fully parameterized techniques, rather than continually loading in large tables of
data containing, information such as number and type of RF pulses to use, to result
in a particular technique. The parameterization may include instructions to be executed
over time and/or until new parameters are provided.
[0024] The EW system may undertake several different categories of operations in electronic
support (ES) and EA techniques. These operations may include, among others, signal
detection, signal identification, and signal tracking during ES and technique development,
technique selection, parameter tracking and effectiveness during EA. Due to the huge
amount of data being processed during a mission, it may be undesirable to offload
processing and decision-making processes to achieve the desired real-time operation
or to be required to load extensive tables of countermeasures. This may be, in particular,
an issue in situations in which an unknown emitter (radar or source of illumination)
actively targets or illuminates the vehicle containing the EW system. The decision
of whether a particular radar is targeting the vehicle may thus depend on the vehicle
detecting illumination (e.g., pulses) received from the emitter at the vehicle.
[0025] The information with which the EW system may have to work may be radio frequency
signal (e.g., pulse) data. Thus, the RF signals alone may be processed by the EW system
to identify the source and determine the nature of the RF signals, whether threatening
or non-threatening, and determine the appropriate action to take. However, the EW
system may receive a tremendous amount of raw observables - millions of pulses/second
- and act upon them in short order. More specifically, the EW system may digitize
the pulses, separate and filter the pulses into individual sources using stored sets
of parameters, match the sources to known radar, assess ambiguities between the known
signals and unknown signals, determine location and probable type and capabilities
of each source, and determine and take appropriate countermeasures for each source.
[0026] FIG. 3 shows a block diagram of EA firmware according to some embodiments. The modules,
which in some embodiments may be embodied as circuitry, include an Analog to Digital
Converter (ADC) 302, a channelizer 304, a channel data demultiplexer 306, a pulse
detector 308, a Pulse Descriptor Word (PDW) module 310, a Pulse Repetition Frequency
(PRF) tracker 312, a Universal Coherent Technique Generator (CTG) 314, an inverse
channelizer 316, a Digital to Analog Converter (DAC) 318, a Time of Arrival Counter
320, a Digital Radio Frequency Memory (DRFM) pulse storage module 322, a Noise/Technique
Generator 324 and a control parameter interface 326. The various modules shown in
the EA firmware 300 may be implemented as individual elements in a field programmable
gate array (FPGA), software and/or separate hardware. In some embodiments, some of
the modules shown, such as the Noise/Technique Generator 324 may not be present. Some
of the modules shown in FIG. 3 may further be disabled, for example, the input modules
containing the ADC 302, channelizer 304 and demultiplexer 306 may not be active when
the receiver shown in FIG. 1 is off.
[0027] When the receiver shown in FIG. 1 is active, RF pulses are received by the EW system.
The RF pulses may be modulated to an intermediate frequency (IF) using a mixer and
filter (not shown) before being passed to the ADC 302. The IF pulses may extend in
all or part of baseband to 800MHz or even beyond 1GHz, for example. The ADC 302 digitizes
the pulses before providing the digitized pulses to the channelizer 304. The channelizer
304 spectrally filters the pulses to create one of sets of pulsed data in a narrow
frequency band. The channelizer 304 may programmable, with the number of bins and
width selectable. In non-exclusive examples, when the IF range is up to 800MHz, the
channelizer 304 may be selected to have 10 80MHz bins (e.g., 0MHz-80MHz, 80MHz-160MHz,
....), 50 16MHz bins or 100 8MHz bins.
[0028] The channelizer 304 output, which may be in parallel, is provided to the demultiplexer
306. Thus, a particular bin, and all pulses from the one or more radar sources that
fit into the bin, is sequentially selected the demultiplexer 306. Although not shown,
at least some of the modules may be provided with a clock signal from a clock to permit
synchronized processing of the pulses. In some embodiments, the demultiplexer 306
may be eliminated. The serial output from the demultiplexer 306 is supplied to the
pulse detector 308 and the DRFM pulse storage module 322.
[0029] The pulse detector 308 may detect whether or not a pulse is present in a predetermined
time window. The pulse detector 308 may, for example, detect whether a signal within
the time window has reached a predetermined amplitude for a predetermined length of
time. The pulse detector 308 may trigger on a rising edge of a pulse.
[0030] The PDW generator 310 determines the type of pulse to be generated as a PRF pattern
using the pulse properties of the pulse provided from the pulse detector 308. The
pulse properties include, for example, pulse width, frequency and amplitude, among
others. The pulse detector 308 indicates the pulse properties using a particular codeword
of predetermined length.
[0031] The PDW output of the pulse detector 308 is supplied to the PRF tracker 312. The
PRF tracker 312 determines whether the PRF pattern matches a supplied template within
a predetermined tolerance. This is to say that the PRF tracker 312 determines from
the pattern of occurrences of the PDW whether the PDW is valid and thus countermeasures
are to be taken. The PRF tracker 312 may be able to determine the validity of the
PDW from as few as two repetitions of the pulse chain or three occurrences of the
pulse (PDW). The PRF tracker 312 may be able to determine the existence of radar pulses
from pulses having a high repetition rate (of, e.g., < 1ms). The combination of the
PRF tracker 312 and the PDW generator 310 may be duplicated a predetermined number
of times.
[0032] The PRF tracker 312 provides ATOA data to the CTG 314 and to the DRFM storage module
322. The ATOA data provides a prediction of the timing of the next pulse so that when
the receiver is not actively receiving pulses, the EW system can nevertheless predict
the arrival of the pulses and respond accordingly. The PDW generator 310, the PRF
tracker 312, the CTG 314 and the DRFM storage module 322 are supplied with timing
information from the TOA counter 320 so that the PDW generator 310, the PRF tracker
312, the CTG 314 and the DRFM storage module 322 are able to act synchronously and
in accordance with the ATOA data. The CTG 314 modifies the current pulse or one or
more stored pulses and retransmits them either before or after the ATOA data. The
captured threat pulses are modified and superposed (or superposed and then modified)
such that multiple threat pulses from either the same radar or different radars and
having either the same characteristics or different characteristics are provided in
response.
[0033] In some embodiments, a Mission Data File is provided to the EA firmware before the
start of a mission. The Mission Data File may define each parameter for different
techniques in a technique message description document, and the parameters provided
via the control parameter interface 326. The Mission Data File may also indicate the
expected patterns of PRF for the PRF tracker 312 to use. In some embodiments, the
PRF tracker 312 or another tracker may discover the PRF pattern autonomously.
[0034] The CTG 314 interprets the parameterized message from the control parameter interface
326 and acts as a technique generator, using several different modifications in series
and/or parallel and subsequently summing the result. The parameter values in the message
content of the Mission Data File are already in a format that the CTG 314 is able
to use. In some embodiments, the Mission Data File, which may be stored in XML or
another file type, may be translated into the memory mapped I/O for the CTG 314. The
CTG 314 may generally accept In-phase (I)/Quadrature-phase (Q) pulse data or real
data, applies one or more modulations per the parameters and provides a streaming
output for the modulated I/Q pulse data. The CTG 314 may receive pulse data directly
through the receiver chain, when the receiver is active, or may retrieve the pulse
data from the DRFM storage module 322 to execute selected techniques, such as when
the receiver is in sleep mode (inactive). In some embodiments, the CTG 314 may transmit
a read request to the DRFM storage module 322 when the ATOA data indicates that pulse
creation is to occur and in response receives the I/Q pulse data from the DRFM storage
module 322. The CTG 314 decomposes coherent techniques into independent building blocks
and that may be scaled to any number of parallel modulations, as shown in more detail
in FIG. 4. The CTG 314 also has the capability to produce partial pulses and to create
a weighted and modulated composition (summation) of multiple pulses.
[0035] Similarly, the DRFM storage module 322 is supplied with the pulse from the channel
demodulator 306, TOA counter information (system timing information) from the TOA
counter 320, ATOA data of the pulse timing from the PRF tracker 312, and pulse data
from the CTG 314, as well as parameters from the control parameter interface 326.
The pulse information may be stored in the DRFM storage module 322 for a relatively
short amount of time prior to being supplied to for response to the threat pulse.
The parameter data may indicate to the DRFM storage module 322, for example, how long
to store a particular pulse type (PDW) as well as what parameters to use for countermeasures.
The DRFM storage module 322 may indicate to the CTG 314 at a particular timing indicated
by the TOA counter 320 the pulse parameters of the threat pulses stored to use in
modifying the stored pulses to counter the received or predicted threat pulses. The
DRFM storage module 322 may store pulses to internal or external memory. The DRFM
storage module 322 may thus arbitrate the pulse timing storage for a particular PDW,
which the CTG 314 is able to recall from the DRFM storage module 322 when desired.
[0036] The control parameter interface 326 provides various parameters to the DRFM storage
module 322, the pulse detector 308, the PDW generator 310, the PRF tracker 312 and
the Noise/Technique Generator 324. The parameters supplied by the control parameter
interface 326 may be received by the control parameter interface 326 through a port
such as a USB or PCI interface, externally over a radio network, or a combination
thereof in various embodiments, for dissemination. For example, the control parameter
interface 326 provides parameters to permit the pulse detector 308 to set the amplitude
and timing for accurate pulse detection, to provide the PDW generator 310 with the
characteristics of various PDWs to permit the PDW generator 310 to match pulse characteristics
with the appropriate PDW, to permit the PRF tracker 312 to determine whether the PDW
is valid, to provide the modulation slope and curve parameters to the CTG 314 to permit
the CTG 314 to generate the appropriate pulses and the Noise/Technique Generator 324
with activation and type of signals to generate for a particular PDW. By providing
the parameters via the control parameter interface 326, the EW system may avoid loading
in large tables of PDWs, reducing the latency. In addition, the parameterization of
the EW system pulses permits rapid reprogramming without the altering the firmware
or the coding of the firmware shown in FIG. 3.
[0037] The pulse data from the CTG 314 is provided to the inverse channelizer 316. In some
circumstances, the Noise/Technique Generator 324 may further modify the pulse data
or create signals prior to or subsequent to the pulse and provide these signals to
an adder to include noise or other EW technique data. The Noise/Technique Generator
324 may be used when the CTG 314 is supplying pulse data. Alternatively, the Noise/Technique
Generator 324 may be used alone, without data from the CTG 314 such that, for example,
only noise is broadcast from the EW system. The inverse channelizer 316 takes the
narrowband signals and creates a single wideband signal, in a manner similar to (but
opposite of) the channelizer 304. Like the channelizer 304, the inverse channelizer
316 is programmable such that the width of the pulse train and the number of bins
is selectable. Typically, the values used in the inverse channelizer 316 may mirror
those of the channelizer 304, although there may be circumstances in which this is
not the case. The inverse channelizer 316 thus turns the narrowband response pulses
into a wideband signal.
[0038] The output from the inverse channelizer 316 is provided to the DAC 318 to provide
an analog IF signal. The IF signal may extend from baseband to 800MHz-1GHz, for example,
symmetric to the ADC 302 or may use a different range. The IF pulses are modulated
to RF using a mixer before being transmitted by the antenna of the EW system.
[0039] FIG. 4 shows the CTG architecture in accordance with some embodiments. In the CTG
architecture 400, the parameters controlling the modules 406, 408, 410, 412, which
in some embodiments may be embodied as circuitry, may be fully parametrized and techniques
may be rapidly updated during real-time operation. The modulation slopes and curves
may be computed at run time rather than being delaying by loading large parameter
tables with parameters to be executed each clock cycle or large tables of precomputed
data samples. The CTG architecture 400 may decompose some or all of the coherent techniques
into independent modulation blocks. The coherent techniques may further be scaled
to any number of parallel modulations. The CTG architecture 400 may provide partial
pulse capability, where a partial pulse is defined as either recording only part of
an incoming pulse or playing back only part of a recorded pulse and the capability
to create a weighted and modulated composition (summation) of multiple pulses.
[0040] Specifically, as shown in the embodiment of FIG. 4, the CTG architecture 400 includes
a pulse memory 402 and pulse stretch 406, range modulation 408, velocity modulation
410 and amplitude modulation 412 modules. Although the modulation modules 406, 408,
410, 412 are shown in a particular order, in other embodiments the order of the modulation
modules 406, 408, 410, 412 may differ. The pulse memory 402 may contain one or more
sets of pulses and provide these pulses to be modified by some or all of the modulation
modules 406, 408, 410, 412. The pulses provided by the pulse memory 402 may have particular
characteristics specific to the threat pulses received so that the threat pulses obtained
over the entire mission may be retained. In some embodiments the pulse memory 402
may be limited such that only a portion of the threat pulses over a mission may be
stored in the pulse memory 402 at any time.
[0041] The pulse stretch module 406 adjusts the pulse length of the signals from the pulse
memory 402, allowing a partial pulse to be applied during a particular time period,
e.g., using a sample-and-hold flipflop. The pulse stretch module 406 allows for playback
of a partial pulse or recorded pulse a programmable number of times. The target pulse
width provided by the pulse stretch module 406 can be selected in a number of ways.
Selection by number results in the target pulse width to be composed of an integral
number of input pulses, using head-to-tail concatenation. A head-to-tail technique
is defined as transmitting copies of a recorded pulse back-to-back continuously such
that the tail of one copy abuts to the head of the next copy in the time domain. The
target pulse width may be selected from modes that include number, width, programmable
and continuous. The number is the number of input pulses that are combined to form
the stretched target pulse. The integral number can be zero for a width less than
the input pulse width. Selection by width gives a target pulse of width that is an
integral number of input pulses plus a fractional part so that the total pulse width
is of the specified value. The width can be smaller or larger than the input pulse.
The stretched pulse can also be constructed from a part of the input pulse by specifying
a start time. The segment of the input pulse delayed from the beginning by the start
time duration and ending at the pulse termination is used in this case to generate
the target pulse of specified width. For width greater than the input pulse segment,
head-to-tail concatenation of the segment is used for pulse generation. For continuous
mode, the input pulse is concatenated head-to-tail to generate a target pulse that
fills up the Pulse Repetition Interval (PRI) of the input pulses. Although a predetermined
number of 32 bit parameters (e.g., 2) may be provided independent of the mode, different
parameters may be used dependent on the mode. For example, if continuous mode is selected,
no parameter may be used as the length is the PRI. If the number mode is selected,
the parameters of number and decimal may be used to determine the pulse length (pulse
length = N.D*PW). If width mode is selected, only one parameter, the time (i.e., width
- e.g., 1 bit = 1µs) may be used to determine the pulse width. If programmable mode
is selected, the width and start time (e.g., 1 bit = 1µs)) may be used to determine
the pulse length.
[0042] The range modulation module 408 provides delay of the pulse through a gate. The range
modulation module 408 retrieves a stretched or partial pulse from memory at certain
time delays, synchronized to the ATOA prediction. In various embodiments, the time
delay can be fixed, random, ramped linearly or ramped parabolically, among others.
The range modulation module 408 has a number of selectable settings such as Range
Gate Stealer/Range Gate Pull Out (RGS/RGPO) with Keeper RGS/RGPO without Keeper, pseudorandom
or Range Bin Masking. A range gate pull out technique is a technique in which the
copied radar threat pulse is played back with successively longer time delays with
a Doppler shift at each of the threat radar's pulse repetition intervals (PRI) such
that on a radar display, it looks like the false target being created by the retransmitted
pulse is getting further away. A keep pulse is defined as a pulse played back immediately
with no time delay. Range bin masking involves retransmitting a copied pulse at arbitrary
time delays where the time delays are defined by a mask (control bits). In RGS/RGPO
mode, the start time is the time that the dwell location is delayed to, the dwell
time is the time that the pulse dwells at the TOA position (coincident with the skin
return of the input radar pulse), the walk time is the time taken for the pulse to
move from the TOA position to the specified range delay position, the hold time is
the time the pulse is held at the range delay position, the walk type indicates whether
the pulse can move from the TOA position to range delay position (OUT mode) or from
the range delay to the TOA position (IN mode), the range delay is the extent the pulse
travels relative to the TOA pulse, the Doppler offset is the Doppler shift impressed
on the RF of the pulse (in coordinated mode, the Doppler offset is a calculated parameter,
whereas for uncoordinated mode, the parameter is specified by the user), the acceleration
should equal 2/9.8*(range delay)/(walk time)
2 and the slope indicates the slope of the linear walk (*(range delay)/(walk time)).
The position of the false target is related to the walk time by the relation. In RGS/RGPO
mode, a linear walk walks a pulse from zero delay (with respect to input TOA pulse)
to maximum delay with constant velocity, continuously repeating this pattern while
a parabolic walk walks the pulse from zero delay to maximum delay with constant acceleration,
continuously repeating this pattern. A plot of pulse position vs time is a parabola
in this case. Depending on the RGS/RGPO mode, a keeper pulse may be a stationary pulse
located at the stop range position. In pseudorandom mode, the pulses are randomly
placed between a specified range within a PRI. In Range Bin Masking mode, the pulses
are randomly placed between specified range values at ranges that are integral multiples
of the range bin size. The eleven parameters used thus may include: start and end
range delay, range bin size, dwell time, walk time, hold time, walk type, range delay,
acceleration, and integer and decimal slope. The settings may be parameterized such
that a number may be used to indicate which range modulation to use.
[0043] The velocity modulation module 410 is used to craft a return that will be interpreted
as having undergone a Doppler effect. The velocity modulation module 410 may thus
add a frequency shift to the output from the range modulation module 408. The frequency
shift delay may be, among others, fixed, random or ramped linearly. The velocity modulation
module 410 settings may include selectable settings including bypass (no modulation
added), fixed (fixed frequency shift applied), Velocity Gate Stealer/Velocity Gate
Pull Out (VGS/VGPO), pseudorandom in which Doppler offsets are randomly placed between
specified frequency values or Velocity Bin Masking in which Doppler offsets are randomly
placed between specified frequency values. In VGS mode, the Doppler shift is linear,
the dwell time is the time duration the Doppler frequency of the pulse is at zero
Doppler offset, the walk time is the time taken for the Doppler offset frequency to
vary from zero offset to the specified offset value, the hold time is the time the
Doppler offset frequency is held at the specified offset frequency, and the Doppler
offset is the final offset value of the frequency during the linear walk cycle. The
seven parameters used thus may include: dwell time, walk time, hold time, Doppler
offset (in which 1 bit = 1 Hz), integer and decimal slope and Doppler bandwidth (in
which 1 bit = 1 Hz). The settings, as above, may be parameterized such that a number
may be used to indicate which velocity modulation to use.
[0044] The amplitude modulation module 412 adjusts the amplitude of the pulses, e.g., through
the use of a multiplier multiplying the pulse. The amplitude modulation module 412
scales the amplitude of the output from velocity modulation module 410 and is synchronized
to the beginning of the transmit window. The modulation period of the amplitude modulation
module 412 is typically several PRIs. One or more types of waveforms may be supported
waveforms include, among others, square, sinusoidal, triangular and sawtooth, as above
selectable using a predetermined value. When multiple signals are being combined,
the amplitude modulation module 412 may decrease the amplitude to limit power to downstream
amplifiers prior to transmission, based on the maximum power useable by the amplifiers
or available to the EW system. The parameters used thus may include: modulation period,
modulation rise time (modulation period * duty cycle), 1/modulation rise time, 1/modulation
fall time (modulation fall time = modulation period - modulation rise time) and modulation
rate.
[0045] An ATOA trigger 404 from the PRF tracker 312 may be used to delay transmission of
the signal from the pulse memory 402 until the appropriate time based on TOA counter
320 to counter the incoming radar through the use of a gate, in particular when the
pulse parameters are provided based on the DRFM pulse storage module 322. In some
embodiments, some or all of the modulation modules 406, 408, 410, 412 to be enabled
for a particular signal supplied by the pulse memory 402.
[0046] As shown in FIG. 4, the CTG architecture 400 may also provide for modulation of multiple
signals in parallel (16 as shown, although this number may vary as desired to be greater
or less than 16) and subsequent signal combination when multiple types of pulses from
one or more radars impinge on the vehicle. When multiple signals are supplied in parallel
through pipes to the modulation modules 406, 408, 410, 412, the signals in the pipes
may be combined at a combiner 414 into a single channel after exiting the last modulation
module so that the signals may be transmitted from an antenna at the same time. The
combiner 414 may be, for example, an adder. The combiner 414 includes a channel arbiter
that accepts I/Q data for each of 4 pipes and a channel mapper. Each of the pipes
may operate on the same channel, on distinct channels, or some combination thereof.
When 2 pipes are operating on the same channel, the I/Q data is divided by 2 on each
channel and then the signals are added together. When 3 to 4 pipes are operating on
the same channel, the I/Q data is divided by 4 on each channel and then the signals
are added together. The channel arbiter outputs pipes on distinct channels of I/Q
data, where some channels may not be used. The channel mapper directs the I/Q data
from the channel arbiter to the proper channel. For example, in a 16 pipe embodiment
if the channel arbiter outputs data on channels 0 and 3, the channel mapper multiplexes
the data to those channels and output zeros on channels 1, 2, and 4-15.
[0047] In one example, the CTG architecture 400 may provide 1 full pulse (no stretch) with
zero delay (time out = ATOA), zero Doppler and a constant amplitude. In another example,
the CTG architecture 400 may provide a delay only case with 1 full pulse (no stretch),
a random delay (pseudorandom pulses), zero Doppler shift, and a constant amplitude.
In a further example, the CTG architecture 400 may provide a first pipe that has a
pulse RGPO with a first velocity and a second pipe that has a different pulse RGPO
with second velocity that is different from the first velocity. In another example,
the pulse stretch module 406 may stretch the pulse by a length of 2.3x and the range
modulation module 408 may have the RGS set to repeat at ATOA + Tus with no modification
being provided by the velocity modulation module 410 or amplitude modulation module
412 for a first pipe; the pulse stretch module 406 may not stretch the pulse and the
range modulation module 408 may be set to Range Bin Masking, with no modification
being provided by the velocity modulation module 410 or amplitude modulation module
412 for a second pipe; the pulse stretch module 406 may not stretch the pulse, the
range modulation module 408 may have the RGS, keeper on, the velocity modulation module
410 may modulate the signal using a velocity gate stealer (VGS) with no modification
being provided by amplitude modulation module 412 for a third pipe; and the pulse
stretch module 406 may continuously stretch the pulse, the range modulation module
408 may not modulate the range, the velocity modulation module 410 may modulate the
signal using VGS mode and the amplitude modulation module 412 may use a sinusoid amplitude
modulation for a fourth pipe before combining the four pipes.
[0048] As above, in some embodiments, the modulation modules 406, 408, 410, 412 may be instantiated
in separate hardware. In other embodiments, the modulation modules 406, 408, 410,
412 may be instantiated in a FPGA and parameterized such that each modulation module
406, 408, 410, 412 may be reprogramed to a different configuration during real time
operation without FPGA reconfiguration. This parameterization may allow selection
between a large variety of EW techniques and options for use in any mission having
its own unique EW mission requirements. The number of EW techniques may vary from
mission to mission and may use different sets of pulses from the pulse memory 402.
The pulse memory 402 may contain all of the pulses for a particular mission or may
be loaded for a particular mission with different sets of pulses if memory is limited.
The logical signal processing architecture for a coherent EA in the CTG architecture
400 may combine multiple types of modulation and combine multiple modulation outputs
on same channels for simultaneous output.
[0049] This is in contrast with existing EW systems, in which new firmware code is written
each time the system performs a new coherent EA technique. Existing technique generators
are largely table-based such that software-based processors compute tables of data
for modulations that are transmitted to firmware components for implementation. In
this case, a finite number of data points are precomputed and loaded into the system.
These approaches may incur high latency and require high levels of I/O between processing
components. The different techniques in this situation are independent and not tightly
coupled with each other.
[0050] In some embodiments, the parameters used in the CTG architecture 400 of FIG. 4 may
be encrypted and decrypted rapidly from the interface or DRFM storage module. Moreover,
due to the layout, the encryption/decryption of the parameters may be undertaken with
a reduced amount of power compared to prior approaches.
[0051] FIG. 5 illustrates EW system response in accordance with some embodiments. Various
operations may be performed by the elements shown in FIGS. 1-4. As shown, at operation
502 pulses are detected by the EW system. The EW system may contain EA firmware/circuitry,
such as that shown in FIGS. 3 and 4. The pulses may be received via one or more antennas,
modulated from RF frequencies to IF frequencies, and converted from a wideband analog
signal to narrowband digital signals in one or more operations. The pulses may then
be detected based on a signal at a particular frequency exceeding a threshold amplitude
for a threshold amount of time.
[0052] At operation 504, after determining that a pulse is present, the EW system determines
whether or not the pulses are valid radar/threat pulses. The EW system may translate
the pulses into one or more predetermined PDW categories (which may be dependent on
the source) and determine whether the PDW fall into a category of valid radar/threat
pulses.
[0053] In the case that one or more radar/threat pulses are present, at operation 506, the
CTG is used to create false pulse responses to the radar/threat pulses when the pulses
are received or at predicted time periods. This may involve generating the pulses
and modulating the pulses using one or more different types of modulation dependent
on the threat, as indicated by a set of parameters stored in the EW system. The generated
pulses may be stretched from a partial pulse period to a continuous stream of pulses,
delayed to a particular response time, Doppler shifted, and amplified. Multiple sets
of pulses from different threats may be simultaneously processed.
[0054] After creating the appropriate false response pulses, at operation 508, the pulses
may be combined and transmitted. In particular, the pulses of different frequencies
may be combined to a wideband signal and then converted to an analog signal prior
to being transmitted from the EW system in response to the threat. In some embodiments,
noise or other techniques may be added prior to being converted to an analog signal.
At times when no response is transmitted, noise may instead be present and being transmitted
so that the noise floor does not change independent of whether the pulse is transmitted.
[0055] Although an embodiment has been described with reference to specific example embodiments,
it will be evident that various modifications and changes may be made to these embodiments
without departing from the broader spirit and scope of the present disclosure. Accordingly,
the specification and drawings are to be regarded in an illustrative rather than a
restrictive sense. The accompanying drawings that form a part hereof show, by way
of illustration, and not of limitation, specific embodiments in which the subject
matter may be practiced. The embodiments illustrated are described in sufficient detail
to enable those skilled in the art to practice the teachings disclosed herein. Other
embodiments may be utilized and derived therefrom, such that structural and logical
substitutions and changes may be made without departing from the scope of this disclosure.
This Detailed Description, therefore, is not to be taken in a limiting sense, and
the scope of various embodiments is defined only by the appended claims, along with
the full range of equivalents to which such claims are entitled.
[0056] In the foregoing Detailed Description, it can be seen that various features are grouped
together in a single embodiment for the purpose of streamlining the disclosure. This
method of disclosure is not to be interpreted as reflecting an intention that the
claimed embodiments require more features than are expressly recited in each claim.
Rather, as the following claims reflect, inventive subject matter lies in less than
all features of a single disclosed embodiment.
1. An electronic warfare 'EW' system (112) comprising:
electronic attack 'EA' circuitry comprising detection circuitry (300) arranged to
detect (502), capture and store threat pulses from a radar (120), pulse generation
circuitry (314, 400) arranged to, in response to identification of the threat pulses,
generate (506) a response comprising a superposition of the threat pulses captured
and stored in memory by at least modulating the threat pulses in amplitude, frequency,
phase, length and timing, wherein modulations of each threat pulse and timing of the
superposition relative to the threat pulses are based on stored parameters, the superposition
comprising response pulses associated with at least one of: threat pulses comprising
different characteristics; and threat pulses originating from different radar; and
transceiver circuitry (112a, 112b) configured to receive the threat pulses and transmit
(508) response pulses of the response;
wherein the pulse generation circuitry (314, 400) comprises a pulse memory (402) arranged
to provide the threat pulses and a plurality of modules comprising:
pulse stretch circuitry (406) arranged to adjust pulse widths of the response pulses
away from pulse widths of the threat pulses;
range modulation circuitry (408) arranged to adjust delays of the response pulses
away from delays of the threat pulses;
velocity modulation circuitry (410) arranged to adjust frequencies of the response
pulses away from frequencies of the threat pulses; and
amplitude modulation circuitry (412) arranged to adjust amplitudes of the response
pulses away from amplitudes of the threat pulses;
wherein the range modulation circuitry (408) is selectable in Range Gate Stealer/Range
Gate Pull Out 'RGS/RGPO' mode in which the response pulses are walked from zero to
maximum delay with one of constant velocity and acceleration and constantly repeated,
RGS/RGPO with Keeper mode that duplicates the RGS/RGPO mode and adds a keeper pulse
at a stop range position of each response pulse, pseudorandom mode in which the response
pulses are randomly placed between a specified range or Range Bin Masking in which
the response pulses are randomly placed between specified range values at ranges that
are integral multiples of a range bin size.
2. The EW system of claim 1, wherein the EA circuitry further comprises timing circuitry
configured to provide predicted timing information of the threat pulses to the pulse
generation circuitry when receiver circuitry of the transceiver circuitry is deactivated
such that the pulse generation circuitry continues to generate the response pulses
at appropriate times and transmitter circuitry of the transceiver circuitry continues
to transmit the response pulses in response to threat pulses that impinge on the EW
system when receiver circuitry of the transceiver circuitry is deactivated.
3. The EW system of claim 1, wherein parameters provided to the pulse stretch circuitry
(406) include an integral number of at least 0 input pulses and a fractional part
to be combined to form a stretched pulse, a start time of pulse generation and a Pulse
Repetition Interval 'PRI'.
4. The EW system of claim 3, wherein the pulse stretch circuitry (406) is selectable
in number mode in which the integral number and fractional part for each response
pulse is received, width mode in which a total pulse width for each response pulse
is received, programmable mode in which a start and end time for each response pulse
is received and continuous mode in which the PRI for each response pulse is received.
5. The EW system of claim 1, wherein the velocity modulation circuitry (410) is selectable
in bypass mode in which no modulation is added, fixed mode in which a fixed frequency
shift is applied to each response pulse, Velocity Gate Stealer/Velocity Gate Pull
Out 'VGS/VGPO' mode in which a linear Doppler shift is applied to each response pulse
such that the response pulses are walked from zero to maximum Doppler shift with constant
velocity and constantly repeated, pseudorandom mode in which Doppler offsets are randomly
placed between specified frequency values for each response pulse or Velocity Bin
Masking in which Doppler offsets are randomly placed between specified frequency values
for each response pulse.
6. The EW system of claim 1, further comprising a combiner (414), wherein the plurality
of modules are duplicated and independent of each other such that each duplicate is
arranged to provide different response pulses from the threat pulses in response to
different threat pulses, the combiner (414) arranged to combine the different response
pulses into a single channel to enable the response pulses to be simultaneously transmitted.
7. The EW system of claim 1, wherein the amplitude modulation circuitry (412) is selectable
in square, sinusoidal, triangular and sawtooth modes.
8. The EW system of claim 1, wherein the EA circuitry further comprises:
tracker circuitry (312) arranged to determine validity of the threat pulses and indicate
to the pulse generation circuitry existence of valid threat pulses; and
noise circuitry (324) arranged to add noise to the response pulses prior to transmission
from the transceiver circuitry (112a, 112b).
9. A method of generating pulses by an electronic warfare system (112) comprising:
detecting (502) and storing threat pulses from at least one radar (120) impinging
on a vehicle (100);
determining (504) that the threat pulses are valid threat pulses;
modulating amplitude, frequency, phase, length and timing of the stored threat pulses
and superposing the modulated threat pulses to generate (506) response pulses to the
threat pulses, modulations of each threat pulse and timing of the superposition relative
to the threat pulses based on stored parameters;
transmitting (508) the response pulses;
providing the threat pulses from a memory;
modulating pulse widths of the response pulses from pulse widths of the threat pulses;
modulating delays of the response pulses from delays of the threat pulses;
modulating frequencies of the response pulses from frequencies of the threat pulses;
modulating amplitudes of the response pulses from amplitudes of the threat pulses;
and
selecting a mode for modifying the delays from a Range Gate Stealer/Range Gate Pull
Out 'RGS/RGPO' mode in which the response pulses are walked from zero to maximum delay
with one of constant velocity and acceleration and constantly repeated, a RGS/RGPO
with Keeper mode that duplicates the RGS/RGPO mode and adds a keeper pulse at a stop
range position of each response pulse, a pseudorandom mode in which the response pulses
are randomly placed between a specified range and a Range Bin Masking in which the
response pulses are randomly placed between specified range values at ranges that
are integral multiples of a range bin size.
10. The method of claim 9, further comprising:
calculating predicted timing of the threat pulses based on reception of the threat
pulses;
disabling reception of the threat pulses; and
continuing to generate response pulses at appropriate times when reception of the
threat pulses is disabled and continuing to transmit the response pulses in response
to threat pulses that impinge on the vehicle when reception of the threat pulses is
disabled.
11. The method of claim 9, further comprising:
providing simultaneous and independent modification paths for modification of pulse
widths, delays, frequencies and amplitudes of the threat pulses in response to identification
of different threat pulses to create (506) different response pulses;
combining the different response pulses into a single channel; and
simultaneously transmitting (508) the different response pulses in the single channel.
12. The method of claim 9, wherein parameters provided to modify the pulse widths of the
response pulses include an integral number of at least 0 input pulses and a fractional
part to be combined to form a stretched pulse, a start time of pulse generation and
a Pulse Repetition Interval 'PRI'.
13. The method of claim 9, and further comprising at least one of:
selecting a mode for modifying the pulse widths from a number mode in which the integral
number and fractional part for each response pulse is received, a width mode in which
a total pulse width for each response pulse is received, a programmable mode in which
a start and end time for each response pulse is received and a continuous mode in
which the PRI for each response pulse is received; and
selecting a mode for modifying frequencies from a bypass mode in which no modulation
is added, fixed mode in which a fixed frequency shift is applied to each response
pulse, a Velocity Gate Stealer/Velocity Gate Pull Out 'VGS/VGPO' mode in which a linear
Doppler shift is applied to each response pulse such that the response pulses are
walked from zero to maximum Doppler shift with constant velocity and constantly repeated,
a pseudorandom mode in which Doppler offsets are randomly placed between specified
frequency values for each response pulse and a Velocity Bin Masking in which Doppler
offsets are randomly placed between specified frequency values for each response pulse.
14. A computer-readable storage medium that stores instructions for execution by one or
more processors of an electronic warfare system (112) to:
detect (502) threat pulses from at least one radar (120);
modulate amplitude, frequency, phase, length and timing of the threat pulses and superposing
the modulated threat pulses to generate (506) response pulses to the threat pulses,
modulations of each threat pulse and timing of the superposition relative to the threat
pulses based on stored parameters;
calculate predicted timing of the threat pulses based on reception of the threat pulses;
disable reception of the threat pulses at predetermined times;
generate (506) response pulses and transmit (508) the response pulses in response
to threat pulses when the threat pulses are received and when reception of the threat
pulses is disabled;
modify characteristics of the threat pulses from initial characteristics of threat
pulses, the characteristics including pulse widths, delays, frequencies and amplitudes;
and
select a mode for modifying the delays from a Range Gate Stealer/Range Gate Pull Out
'RGS/RGPO' mode in which the response pulses are walked from zero to maximum delay
with one of constant velocity and acceleration and constantly repeated, a RGS/RGPO
with Keeper mode that duplicates the RGS/RGPO mode and adds a keeper pulse at a stop
range position of each response pulse, a pseudorandom mode in which the response pulses
are randomly placed between a specified range and a Range Bin Masking in which the
response pulses are randomly placed between specified range values at ranges that
are integral multiples of a range bin size.
15. The medium of claim 14, wherein the one or more processors further:
provide simultaneous and independent modification paths for modification of pulse
widths, delays, frequencies and amplitudes of the threat pulses in response to identification
of different threat pulses to create (506) different response pulses;
combine the different response pulses into a single channel; and
simultaneously transmit (508) the different response pulses in the single channel.
1. Elektronisches Kriegsführungssystem (electronic warfare - "EW") (112), Folgendes umfassend:
eine elektronische Angriffsschaltung (electronic attack - "EA"), umfassend eine Erkennungsschaltung
(300), die dazu angeordnet ist, Bedrohungsimpulse von einem Radargerät (120) zu erkennen
(502), zu erfassen und zu speichern, eine Impulsgenerierungsschaltung (314, 400),
die dazu angeordnet ist, als Antwort auf die Identifizierung der Bedrohungsimpulse
eine Antwort zu generieren (506), die eine Überlagerung der erfassten und im Speicher
gespeicherten Bedrohungsimpulse umfasst, indem mindestens die Bedrohungsimpulse in
Amplitude, Frequenz, Phase, Länge und Timing moduliert werden, wobei Modulationen
jedes Bedrohungsimpulses und das Timing der Überlagerung relativ zu den Bedrohungsimpulsen
auf gespeicherten Parametern basieren, wobei die Überlagerung Antwortimpulse umfasst,
die mindestens einem von Folgendem zugeordnet sind: Bedrohungsimpulse, die unterschiedliche
Merkmale umfassen; und Bedrohungsimpulse, die von verschiedenen Radargeräten ausgehen;
und
eine Transceiver-Schaltung (112a, 112b), die konfiguriert ist, um die Bedrohungsimpulse
zu empfangen und Antwortimpulse der Antwort zu senden (508);
wobei die Impulsgenerierungsschaltung (314, 400) einen Impulsspeicher (402), der angeordnet
ist, um die Bedrohungsimpulse bereitzustellen, und eine Vielzahl von Modulen umfasst,
die Folgendes umfassen:
eine Impulsdehnungsschaltung (406), die angeordnet ist, um die Impulsbreiten der Antwortimpulse
so einzustellen, dass sie sich von den Impulsbreiten der Bedrohungsimpulse entfernen;
eine Bereichsmodulationsschaltung (408), die angeordnet ist, um die Verzögerungen
der Antwortimpulse so einzustellen, dass sie sich von den Verzögerungen der Bedrohungsimpulse
entfernen;
eine Geschwindigkeitsmodulationsschaltung (410), die angeordnet ist, um die Frequenzen
der Antwortimpulse so einzustellen, dass sie sich von den Frequenzen der Bedrohungsimpulse
entfernen; und eine Amplitudenmodulationsschaltung (412), die angeordnet ist, um die
Amplituden der Antwortimpulse so einzustellen, dass sie sich von den Amplituden der
Bedrohungsimpulse entfernen;
wobei die Bereichsmodulationsschaltung (408) im "RGS/RGPO"-Modus ("Range Gate Stealer/Range
Gate Pull Out"), in dem die Antwortimpulse mit einer von konstanter Geschwindigkeit
und Beschleunigung von Null bis zur maximalen Verzögerung durchlaufen und ständig
wiederholt werden, im Modus RGS/RGPO mit Keeper, der den RGS/RGPO-Modus dupliziert
und einen Keeper-Impuls an einer Stoppbereichsposition jedes Antwortimpulses hinzufügt,
im Pseudozufallsmodus, in dem die Antwortimpulse zufällig zwischen einem angegebenen
Bereich platziert werden, oder in der Range-Bin-Maskierung, in der die Antwortimpulse
zufällig zwischen angegebenen Bereichswerten in Bereichen platziert werden, die ganzzahlige
Vielfache einer Range-Bin-Größe sind, auswählbar ist.
2. EW-System nach Anspruch 1, wobei die EA-Schaltung ferner eine Timing-Schaltung umfasst,
die konfiguriert ist, um vorhergesagte Timing-Informationen der Bedrohungsimpulse
für die Impulsgenerierungsschaltung bereitzustellen, wenn die Empfängerschaltung der
Transceiver-Schaltung deaktiviert ist, sodass die Impulsgenerierungsschaltung weiterhin
die Antwortimpulse zu geeigneten Zeitpunkten generiert und die Senderschaltung der
Transceiver-Schaltung weiterhin die Antwortimpulse als Antwort auf Bedrohungsimpulse
sendet, die auf das EW-System auftreffen, wenn die Empfängerschaltung der Transceiver-Schaltung
deaktiviert ist.
3. EW-System nach Anspruch 1, wobei für die Impulsdehnungsschaltung (406) bereitgestellte
Parameter eine ganze Zahl von mindestens 0 Eingangsimpulsen und einen Bruchteil, der
zur Bildung eines gedehnten Impulses kombiniert werden soll, eine Startzeit der Impulsgenerierung
und ein Impulswiederholungsintervall "PRI" beinhalten.
4. EW-System nach Anspruch 3, wobei die Impulsdehnungsschaltung (406) im Zahlenmodus,
in dem die ganze Zahl und der Bruchteil für jeden Antwortimpuls empfangen wird, im
Breitenmodus, in dem eine Gesamtimpulsbreite für jeden Antwortimpuls empfangen wird,
im programmierbaren Modus, in dem eine Start- und Endzeit für jeden Antwortimpuls
empfangen wird, und im kontinuierlichen Modus, in dem das PRI für jeden Antwortimpuls
empfangen wird, auswählbar ist.
5. EW-System nach Anspruch 1, wobei die Geschwindigkeitsmodulationsschaltung (410) im
Bypass-Modus, in dem keine Modulation hinzugefügt wird, im festen Modus, in dem eine
feste Frequenzverschiebung auf jeden Antwortimpuls angewendet wird, im "VGS/VGPO"-Modus
("Velocity Gate Stealer/Velocity Gate Pull Out"), in dem eine lineare Doppler-Verschiebung
auf jeden Antwortimpuls angewendet wird, sodass die Antwortimpulse mit konstanter
Geschwindigkeit von Null bis zur maximalen Doppler-Verschiebung durchlaufen und ständig
wiederholt werden, im Pseudozufallsmodus, in dem Doppler-Versätze zufällig zwischen
angegebenen Frequenzwerten für jeden Antwortimpuls platziert werden, oder in der Velocity-Bin-Maskierung,
in der Doppler-Versätze zufällig zwischen angegebenen Frequenzwerten für jeden Antwortimpuls
platziert werden, auswählbar ist.
6. EW-System nach Anspruch 1, das ferner einen Kombinator (414) umfasst, wobei die Vielzahl
von Modulen dupliziert und unabhängig voneinander sind, sodass jedes Duplikat so angeordnet
ist, dass es als Antwort auf unterschiedliche Bedrohungsimpulse unterschiedliche Antwortimpulse
von den Bedrohungsimpulsen bereitstellt, wobei der Kombinator (414) so angeordnet
ist, dass er die verschiedenen Antwortimpulse in einen einzigen Kanal kombiniert,
um das gleichzeitige Senden der Antwortimpulse zu ermöglichen.
7. EW-System nach Anspruch 1, wobei die Amplitudenmodulationsschaltung (412) im Quadrat-,
Sinus-, Dreieck- und Sägezahn-Modus auswählbar ist.
8. EW-System nach Anspruch 1, wobei die EA-Schaltung ferner Folgendes umfasst:
eine Verfolgungsschaltung (312), die angeordnet ist, um die Gültigkeit der Bedrohungsimpulse
zu bestimmen und der Impulsgenerierungsschaltung das Vorhandensein gültiger Bedrohungsimpulse
anzuzeigen; und
eine Rauschschaltung (324), die angeordnet ist, um den Antwortimpulsen vor dem Senden
von der Transceiver-Schaltung (112a, 112b) Rauschen hinzuzufügen.
9. Verfahren zum Generieren von Impulsen durch ein elektronisches Kriegsführungssystem
(112), Folgendes umfassend:
Erkennen (502) und Speichern von Bedrohungsimpulsen von mindestens einem Radargerät
(120), die auf ein Fahrzeug (100) auftreffen;
Bestimmen (504), dass die Bedrohungsimpulse gültige Bedrohungsimpulse sind;
Modulieren von Amplitude, Frequenz, Phase, Länge und Timing der gespeicherten Bedrohungsimpulse
und Überlagern der modulierten Bedrohungsimpulse, um Antwortimpulse auf die Bedrohungsimpulse
zu generieren (506), wobei Modulationen jedes Bedrohungsimpulses und das Timing der
Überlagerung relativ zu den Bedrohungsimpulsen basierend auf gespeicherten Parametern
sind; Senden (508) der Antwortimpulse;
Bereitstellen der Bedrohungsimpulse aus einem Speicher;
Modulieren der Impulsbreiten der Antwortimpulse aus den Impulsbreiten der Bedrohungsimpulse;
Modulieren der Verzögerungen der Antwortimpulse aus den Verzögerungen der Bedrohungsimpulse;
Modulieren der Frequenzen der Antwortimpulse aus den Frequenzen der Bedrohungsimpulse;
Modulieren der Amplituden der Antwortimpulse aus den Amplituden der Bedrohungsimpulse;
und
Auswählen eines Modus zum Modifizieren der Verzögerungen aus einem "RGS/RGPO"-Modus
("Range Gate Stealer/Range Gate Pull Out"), in dem die Antwortimpulse mit einer von
konstanter Geschwindigkeit und Beschleunigung von Null bis zur maximalen Verzögerung
durchlaufen und ständig wiederholt werden, einem Modus RGS/RGPO mit Keeper, der den
RGS/RGPO-Modus dupliziert und einen Keeper-Impuls an einer Stoppbereichsposition jedes
Antwortimpulses hinzufügt, einem Pseudozufallsmodus, in dem die Antwortimpulse zufällig
zwischen einem angegebenen Bereich platziert werden, und einer Range-Bin-Maskierung,
in der die Antwortimpulse zufällig zwischen angegebenen Bereichswerten in Bereichen
platziert werden, die ganzzahlige Vielfache einer Range-Bin-Größe sind.
10. Verfahren nach Anspruch 9, ferner Folgendes umfassend:
Berechnen des vorhergesagten Timings der Bedrohungsimpulse basierend auf dem Empfang
der Bedrohungsimpulse;
Deaktivieren des Empfangs der Bedrohungsimpulse; und
Fortsetzen des Generierens von Antwortimpulsen zu geeigneten Zeitpunkten, wenn der
Empfang der Bedrohungsimpulse deaktiviert ist, und Fortsetzen des Sendens der Antwortimpulse
als Antwort auf Bedrohungsimpulse, die auf das Fahrzeug auftreffen, wenn der Empfang
der Bedrohungsimpulse deaktiviert ist.
11. Verfahren nach Anspruch 9, ferner Folgendes umfassend:
Bereitstellen gleichzeitiger und unabhängiger Modifikationspfade zur Modifikation
von Impulsbreiten, Verzögerungen, Frequenzen und Amplituden der Bedrohungsimpulse
als Antwort auf die Identifizierung verschiedener Bedrohungsimpulse, um unterschiedliche
Antwortimpulse zu erzeugen (506);
Kombinieren der verschiedenen Antwortimpulse in einen einzigen Kanal; und
gleichzeitiges Senden (508) der verschiedenen Antwortimpulse in dem einzigen Kanal.
12. Verfahren nach Anspruch 9, wobei Parameter, die zum Modifizieren der Impulsbreiten
der Antwortimpulse bereitgestellt werden, eine ganze Zahl von mindestens 0 Eingangsimpulsen
und einen Bruchteil, der zur Bildung eines gedehnten Impulses kombiniert werden soll,
eine Startzeit der Impulsgenerierung und ein Impulswiederholungsintervall "PRI" beinhalten.
13. Verfahren nach Anspruch 9, und ferner mindestens eines von Folgendem umfassend:
Auswählen eines Modus zum Modifizieren der Impulsbreiten aus einem Zahlenmodus, in
dem die ganze Zahl und der Bruchteil für jeden Antwortimpuls empfangen werden, einem
Breitenmodus, in dem eine Gesamtimpulsbreite für jeden Antwortimpuls empfangen wird,
einem programmierbaren Modus, in dem eine Start- und Endzeit für jeden Antwortimpuls
empfangen werden, und einem kontinuierlichen Modus, in dem das PRI für jeden Antwortimpuls
empfangen wird; und
Auswählen eines Modus zum Modifizieren von Frequenzen aus einem Bypass-Modus, in dem
keine Modulation hinzugefügt wird, einem festen Modus, in dem eine feste Frequenzverschiebung
auf jeden Antwortimpuls angewendet wird, einem "VGS/VGPO"-Modus ("Velocity Gate Stealer/Velocity
Gate Pull Out"), in dem eine lineare Doppler-Verschiebung auf jeden Antwortimpuls
angewendet wird, sodass die Antwortimpulse mit konstanter Geschwindigkeit von Null
bis zur maximalen Doppler-Verschiebung durchlaufen und ständig wiederholt werden,
einem Pseudozufallsmodus, in dem Doppler-Versätze zufällig zwischen angegebenen Frequenzwerten
für jeden Antwortimpuls platziert werden, und einer Velocity-Bin-Maskierung, in der
Doppler-Versätze zufällig zwischen angegebenen Frequenzwerten für jeden Antwortimpuls
platziert werden.
14. Computerlesbares Speichermedium, das Anweisungen zur Ausführung durch einen oder mehrere
Prozessoren eines elektronischen Kriegsführungssystems (112) speichert, zum:
Erkennen (502) von Bedrohungsimpulsen von mindestens einem Radargerät (120);
Modulieren von Amplitude, Frequenz, Phase, Länge und Timing der Bedrohungsimpulse
und Überlagern der modulierten Bedrohungsimpulse, um Antwortimpulse auf die Bedrohungsimpulse
zu generieren (506), wobei Modulationen jedes Bedrohungsimpulses und das Timing der
Überlagerung relativ zu den Bedrohungsimpulsen basierend auf gespeicherten Parametern
sind; Berechnen des vorhergesagten Timings der Bedrohungsimpulse basierend auf dem
Empfang der Bedrohungsimpulse;
Deaktivieren des Empfangs der Bedrohungsimpulse zu vorgegebenen Zeiten;
Generieren (506) von Antwortimpulsen und Senden (508) der Antwortimpulse als Antwort
auf Bedrohungsimpulse, wenn die Bedrohungsimpulse empfangen werden und wenn der Empfang
der Bedrohungsimpulse deaktiviert ist;
Modifizieren der Merkmale der Bedrohungsimpulse ausgehend von den ursprünglichen Merkmalen
der Bedrohungsimpulse, wobei die Merkmale Impulsbreiten, Verzögerungen, Frequenzen
und Amplituden beinhalten; und
Auswählen eines Modus zum Modifizieren der Verzögerungen aus einem "RGS/RGPO"-Modus
("Range Gate Stealer/Range Gate Pull Out"), in dem die Antwortimpulse mit einer von
konstanter Geschwindigkeit und Beschleunigung von Null bis zur maximalen Verzögerung
durchlaufen und ständig wiederholt werden, einem Modus RGS/RGPO mit Keeper, der den
RGS/RGPO-Modus dupliziert und einen Keeper-Impuls an einer Stoppbereichsposition jedes
Antwortimpulses hinzufügt, einem Pseudozufallsmodus, in dem die Antwortimpulse zufällig
zwischen einem angegebenen Bereich platziert werden, und einer Range-Bin-Maskierung,
in der die Antwortimpulse zufällig zwischen angegebenen Bereichswerten in Bereichen
platziert werden, die ganzzahlige Vielfache einer Range-Bin-Größe sind.
15. Medium nach Anspruch 14, wobei der eine oder die mehreren Prozessoren ferner:
gleichzeitige und unabhängige Modifikationspfade zur Modifikation von Impulsbreiten,
Verzögerungen, Frequenzen und Amplituden der Bedrohungsimpulse als Antwort auf die
Identifizierung verschiedener Bedrohungsimpulse bereitstellen, um unterschiedliche
Antwortimpulse zu erzeugen (506);
die verschiedenen Antwortimpulse in einen einzigen Kanal kombinieren; und
die verschiedenen Antwortimpulse gleichzeitig in dem einzigen Kanal senden (508).
1. Système de guerre électronique « EW » (112) comprenant :
des circuits d'attaque électronique « EA » comprenant des circuits de détection (300)
agencés pour détecter (502), capturer et stocker des impulsions de menace provenant
d'un radar (120), des circuits de génération d'impulsions (314, 400) agencés, en réponse
à l'identification des impulsions de menace, pour générer (506) une réponse comprenant
une superposition des impulsions de menace capturées et stockées en mémoire en modulant
au moins les impulsions de menace en amplitude, fréquence, phase, longueur et synchronisation,
dans lequel les modulations de chaque impulsion de menace et la synchronisation de
la superposition par rapport aux impulsions de menace sont basées sur des paramètres
stockés, la superposition comprenant des impulsions de réponse associées à au moins
l'une parmi : des impulsions de menace comprenant différentes caractéristiques ;
et des impulsions de menace provenant de différents radars ; et des circuits d'émetteur-récepteur
(112a, 112b) configurés pour recevoir les impulsions de menace et transmettre (508)
des impulsions de réponse de la réponse ;
dans lequel les circuits de génération d'impulsions (314, 400) comprennent une mémoire
d'impulsions (402) agencée pour fournir les impulsions de menace et une pluralité
de modules comprenant :
des circuits d'étirement d'impulsion (406) agencés pour ajuster les largeurs d'impulsion
des impulsions de réponse en les éloignant des largeurs d'impulsion des impulsions
de menace ;
des circuits de modulation de plage (408) agencés pour ajuster les retards des impulsions
de réponse en les éloignant des retards des impulsions de menace ;
des circuits de modulation de vitesse (410) agencés pour ajuster les fréquences des
impulsions de réponse en les éloignant des fréquences des impulsions de menace ; et
des circuits de modulation d'amplitude (412) agencés pour ajuster les amplitudes des
impulsions de réponse en les éloignant des amplitudes des impulsions de menace ;
dans lequel les circuits de modulation de plage (408) peuvent être sélectionnés parmi
un mode Range Gate Stealer/Range Gate Pull Out « RGS/RGPO » dans lequel les impulsions
de réponse sont parcourues d'un retard nul à maximal avec une parmi une vitesse et
une accélération constantes et constamment répétées, un mode RGS/RGPO avec maintien
qui duplique le mode RGS/RGPO et ajoute une impulsion de maintien à une position de
plage d'arrêt de chaque impulsion de réponse, un mode pseudo-aléatoire dans lequel
les impulsions de réponse sont placées de manière aléatoire entre une plage spécifiée
ou un masquage de groupe de plages dans lequel les impulsions de réponse sont placées
de manière aléatoire entre des valeurs de plage spécifiées à des plages qui sont des
multiples entiers de la taille d'un groupe de plages.
2. Système EW selon la revendication 1, dans lequel les circuits EA comprennent en outre
des circuits de synchronisation configurés pour fournir des informations de synchronisation
prédites des impulsions de menace aux circuits de génération d'impulsions lorsque
les circuits de réception des circuits d'émetteur-récepteur sont désactivés de telle
sorte que les circuits de génération d'impulsions continuent à générer les impulsions
de réponse à des moments appropriés et les circuits d'émetteur des circuits d'émetteur-récepteur
continuent de transmettre les impulsions de réponse en réponse aux impulsions de menace
qui frappent le système EW lorsque les circuits de récepteur des circuits d'émetteur-récepteur
sont désactivés.
3. Système EW selon la revendication 1, dans lequel les paramètres fournis aux circuits
d'étirement d'impulsion (406) comprennent un nombre entier d'au moins 0 impulsion
d'entrée et une partie fractionnaire à combiner pour former une impulsion étirée,
un temps de début de génération d'impulsion et un intervalle de répétition d'impulsions
« PRI ».
4. Système EW selon la revendication 3, dans lequel les circuits d'étirement d'impulsion
(406) peuvent être sélectionnés parmi un mode numérique dans lequel le nombre entier
et la partie fractionnaire de chaque impulsion de réponse sont reçus, un mode largeur
dans lequel une largeur d'impulsion totale pour chaque impulsion de réponse est reçue
et un mode programmable dans lequel une heure de début et de fin pour chaque impulsion
de réponse est reçue et un mode continu dans lequel le PRI pour chaque impulsion de
réponse est reçu.
5. Système EW selon la revendication 1, dans lequel les circuits de modulation de vitesse
(410) peuvent être sélectionnés parmi un mode contournement dans lequel aucune modulation
n'est ajoutée, un mode fixe dans lequel un décalage de fréquence fixe est appliqué
à chaque impulsion de réponse, un mode Velocity Gate Stealer/Velocity Gate Pull Out
« VGS/VGPO » dans lequel un décalage Doppler linéaire est appliqué à chaque impulsion
de réponse de telle sorte que les impulsions de réponse passent d'un décalage Doppler
nul à maximal avec une vitesse constante et constamment répété et un mode pseudo-aléatoire
dans lequel les décalages Doppler sont placés de manière aléatoire entre des valeurs
de fréquence spécifiées pour chaque impulsion de réponse ou un masquage de groupe
de vitesses dans lequel les décalages Doppler sont placés de manière aléatoire entre
les valeurs de fréquence spécifiées pour chaque impulsion de réponse.
6. Système EW selon la revendication 1, comprenant en outre un combineur (414), dans
lequel la pluralité de modules sont dupliqués et indépendants les uns des autres de
telle sorte que chaque duplicata est agencé pour fournir des impulsions de réponse
différentes des impulsions de menace en réponse à différentes impulsions de menace,
le combineur (414) étant agencé pour combiner les différentes impulsions de réponse
en un seul canal pour permettre aux impulsions de réponse d'être transmises simultanément.
7. Système EW selon la revendication 1, dans lequel les circuits de modulation d'amplitude
(412) peuvent être sélectionnés parmi des modes carré, sinusoïdal, triangulaire et
en dents de scie.
8. Système EW selon la revendication 1, dans lequel les circuits EA comprennent en outre
:
des circuits de suivi (312) agencés pour déterminer la validité des impulsions de
menace et indiquer aux circuits de génération d'impulsions l'existence d'impulsions
de menace valides ; et
des circuits de bruit (324) agencés pour ajouter du bruit aux impulsions de réponse
avant la transmission à partir des circuits d'émetteur-récepteur (112a, 112b).
9. Procédé de génération d'impulsions par un système de guerre électronique (112) comprenant
:
la détection (502) et le stockage d'impulsions de menace provenant d'au moins un radar
(120) frappant un véhicule (100) ;
la détermination (504) que les impulsions de menace sont des impulsions de menace
valides ;
la modulation de l'amplitude, de la fréquence, de la phase, de la longueur et de la
synchronisation des impulsions de menace stockées et la superposition des impulsions
de menace modulées pour générer (506) des impulsions de réponse aux impulsions de
menace, des modulations de chaque impulsion de menace et la synchronisation de la
superposition par rapport aux impulsions de menace sur la base de paramètres stockés
;
la transmission (508) des impulsions de réponse ;
la fourniture des impulsions de menace à partir d'une mémoire ;
la modulation des largeurs d'impulsion des impulsions de réponse par rapport à des
largeurs d'impulsion des impulsions de menace ;
la modulation des retards des impulsions de réponse par rapport à des retards des
impulsions de menace ;
la modulation des fréquences des impulsions de réponse par rapport à des fréquences
des impulsions de menace ;
la modulation des amplitudes des impulsions de réponse par rapport à des amplitudes
des impulsions de menace ; et
la sélection d'un mode pour modifier les retards d'un mode Range Gate Stealer/Range
Gate Pull Out « RGS/RGPO » dans lequel les impulsions de réponse sont parcourues d'un
retard nul à maximal avec une parmi une vitesse et une accélération constantes et
constamment répétées, d'un mode RGS/RGPO avec maintien qui duplique le mode RGS/RGPO
et ajoute une impulsion de maintien à une position de plage d'arrêt de chaque impulsion
de réponse, d'un mode pseudo-aléatoire dans lequel les impulsions de réponse sont
placées de manière aléatoire entre une plage spécifiée ou d'un masquage de groupe
de plages dans lequel les impulsions de réponse sont placées de manière aléatoire
entre des valeurs de plage spécifiées à des plages qui sont des multiples entiers
de la taille d'un groupe de plages.
10. Procédé selon la revendication 9, comprenant en outre :
le calcul du moment prévu des impulsions de menace sur la base de la réception des
impulsions de menace ;
la désactivation de la réception des impulsions de menace ; et
la poursuite de la génération des impulsions de réponse à des moments appropriés lorsque
la réception des impulsions de menace est désactivée et la poursuite de la transmission
des impulsions de réponse en réponse aux impulsions de menace qui frappent le véhicule
lorsque la réception des impulsions de menace est désactivée.
11. Procédé selon la revendication 9, comprenant en outre :
la fourniture de chemins de modification simultanés et indépendants pour modifier
les largeurs, les retards, les fréquences et les amplitudes d'impulsion des impulsions
de menace en réponse à l'identification de différentes impulsions de menace pour créer
(506) différentes impulsions de réponse ;
la combinaison des différentes impulsions de réponse en un seul canal ; et
la transmission simultanée (508) des différentes impulsions de réponse dans le canal
unique.
12. Procédé selon la revendication 9, dans lequel les paramètres fournis pour modifier
les largeurs d'impulsion des impulsions de réponse comportent un nombre entier d'au
moins 0 impulsion d'entrée et une partie fractionnaire à combiner pour former une
impulsion étirée, un temps de début de génération d'impulsion et un intervalle de
répétition d'impulsions « PRI ».
13. Procédé selon la revendication 9, et comprenant en outre au moins l'un de :
la sélection d'un mode pour modifier les largeurs d'impulsion à partir d'un mode numérique
dans lequel le nombre entier et la partie fractionnaire de chaque impulsion de réponse
sont reçus, d'un mode de largeur dans lequel une largeur d'impulsion totale pour chaque
impulsion de réponse est reçue et d'un mode programmable dans lequel une heure de
début et de fin pour chaque impulsion de réponse est reçue et un mode continu dans
lequel le PRI pour chaque impulsion de réponse est reçu ; et
la sélection d'un mode pour modifier les fréquences à partir d'un mode de contournement
dans lequel aucune modulation n'est ajoutée, d'un mode fixe dans lequel un décalage
de fréquence fixe est appliqué à chaque impulsion de réponse, d'un mode Velocity Gate
Stealer/Velocity Gate Pull Out « VGS/VGPO » dans lequel un décalage Doppler linéaire
est appliqué à chaque impulsion de réponse de telle sorte que les impulsions de réponse
passent d'un décalage Doppler nul à maximal avec une vitesse constante et constamment
répété et d'un mode pseudo-aléatoire dans lequel les décalages Doppler sont placés
de manière aléatoire entre des valeurs de fréquence spécifiées pour chaque impulsion
de réponse et d'un masquage de groupe de vitesses dans lequel les décalages Doppler
sont placés de manière aléatoire entre les valeurs de fréquence spécifiées pour chaque
impulsion de réponse.
14. Support de stockage lisible par ordinateur qui stocke des instructions à exécuter
par un ou plusieurs processeurs d'un système de guerre électronique (112) pour :
détecter (502) des impulsions de menace provenant d'au moins un radar (120) ;
moduler l'amplitude, la fréquence, la phase, la longueur et la synchronisation des
impulsions de menace et la superposition des impulsions de menace modulées pour générer
(506) des impulsions de réponse aux impulsions de menace, des modulations de chaque
impulsion de menace et la synchronisation de la superposition par rapport aux impulsions
de menace sur la base de paramètres stockés ;
calculer le moment prévu des impulsions de menace sur la base de la réception des
impulsions de menace ;
désactiver la réception des impulsions de menace à des moments prédéterminés ;
générer (506) des impulsions de réponse et transmettre (508) les impulsions de réponse
en réponse aux impulsions de menace lorsque les impulsions de menace sont reçues et
lorsque la réception des impulsions de menace est désactivée ;
modifier des caractéristiques des impulsions de menace à partir des caractéristiques
initiales des impulsions de menace, les caractéristiques comportant les largeurs,
les retards, les fréquences et les amplitudes d'impulsion ; et
sélectionner un mode pour modifier les retards d'un mode Range Gate Stealer/Range
Gate Pull Out « RGS/RGPO » dans lequel les impulsions de réponse sont parcourues d'un
retard nul à maximal avec une parmi une vitesse et une accélération constantes et
constamment répétées, un mode RGS/RGPO avec maintien qui duplique le mode RGS/RGPO
et ajoute une impulsion de maintien à une position de plage d'arrêt de chaque impulsion
de réponse, un mode pseudo-aléatoire dans lequel les impulsions de réponse sont placées
de manière aléatoire entre une plage spécifiée ou un masquage de groupe de plages
dans lequel les impulsions de réponse sont placées de manière aléatoire entre des
valeurs de plage spécifiées à des plages qui sont des multiples entiers de la taille
d'un groupe de plages.
15. Support selon la revendication 14, dans lequel les un ou plusieurs processeurs en
outre :
fournissent des chemins de modification simultanés et indépendants pour modifier les
largeurs, les retards, les fréquences et les amplitudes d'impulsion des impulsions
de menace en réponse à l'identification de différentes impulsions de menace pour créer
(506) différentes impulsions de réponse ;
combinent les différentes impulsions de réponse en un seul canal ; et
transmettent simultanément (508) les différentes impulsions de réponse dans le canal
unique.